Wireless Local Area Networks (LANs) represented by Institute of Electrical and Electronics Engineers (IEEE) 802.11 have become widespread in recent years, and wireless communication devices compatible with wireless LANs are increasing accordingly. In this regard, in order to improve communication efficiency of individual wireless communication devices and an entire network, the IEEE 802.11 standard is still currently being expanded.
As an example of the extension of the standard, Multi-User Multi-Input Multi-Output (MU-MIMO) for downlink (DL) is employed in the 802.11ac standard. MU-MIMO is a technique that enables a plurality of signals to be transmitted in the same time zone at the same frequency through space division multiplexing.
Here, a range of transmission power that can be set in wireless communication devices is generally regulated in accordance with a law or the like for each region. For this reason, wireless communication devices transmit radio waves at the transmission power according to the regulation.
For example, a technique in which, in a network configured with a slave device and a base station, the slave device transmits baseband a range of transmission power which is settable by the slave device (hereinafter also referred to as a “transmission output adjustable range”) to the base station, and the base station gives a notification indicating a maximum transmission power of each region and a reduction request value of transmission power to the slave device is disclosed in Non-Patent Literatures 1 and 2.
Further, since the number of wireless communication devices is increasing as described above, it is desired to efficiently perform signaling for transmission power control disclosed in Non-Patent Literatures 1 and 2.
On the other hand, for example, a communication system in which a base station groups a plurality of slave devices to be connected and perform signaling for transmission power control in units of groups is disclosed in Patent Literature 1.